import streamlit as st
import pandas as pd
import numpy as np
from io import StringIO
import sys
from sklearn.model_selection import train_test_split
from sklearn.preprocessing import StandardScaler, LabelEncoder
from sklearn.metrics import accuracy_score, classification_report, confusion_matrix
from imblearn.over_sampling import SMOTE
from sklearn.linear_model import LogisticRegression
from sklearn.svm import SVC
import optuna
from sklearn.preprocessing import PolynomialFeatures

# Page configuration
st.set_page_config(page_title="Predictive Modelling", layout="wide")

# Title with centered alignment
st.markdown(
    """
    <h1 style="text-align: center; color: white;">📱 Predictive Model Creation and Evaluation 💻</h1>
    """,
    unsafe_allow_html=True
)

# Flowchart title
st.markdown(
    """
    <h1 style="text-align: center; color: white;">Model Creation Flow</h1>
    """,
    unsafe_allow_html=True
)

st.markdown(
    """
    <div style="text-align: center;">
        <img src="https://cdn-uploads.huggingface.co/production/uploads/67441c51a784a9d15cb12871/g-lmBAPoAV_5uO_fpqFYc.gif" alt="model-creation-flowchart.gif" width="70%" />
    </div>
    """,
    unsafe_allow_html=True
)

df = st.session_state.get("dataset")

# Exclude 'ProductID' from the dataset
if df is not None:
    df = df.drop(columns=['ProductID'], errors='ignore')  # Exclude 'ProductID' if it exists

    st.subheader("Dataset Preview:")
    st.write(df.head())

    # Dropping unnecessary columns
    df.drop(['age_bins', 'ProductPriceBucket', 'CustomerAgeGroup'], axis=1, inplace=True, errors='ignore')
    st.write(df.head())

    # Splitting Feature Variables and Class Labels
    st.markdown("### Split Feature Variables and Class Labels")
    fv = df.iloc[:, :-1]
    cv = df.iloc[:, -1]
    st.write(fv)
    st.write(cv)

    # Feature Engineering
    st.markdown("### Feature Engineering")
    label_encoder = LabelEncoder()
    fv['ProductBrand'] = label_encoder.fit_transform(fv['ProductBrand'])
    fv['ProductCategory'] = label_encoder.fit_transform(fv['ProductCategory'])
    st.write(fv.head())

    # Polynomial Featurisation for Non-Linearity
    st.markdown("### Polynomial Featurisation for Non-Linearity:")
    numeric_columns = fv.select_dtypes(include=[float, int]).columns
    degree = 2
    poly = PolynomialFeatures(degree=degree, include_bias=False)
    poly_features = poly.fit_transform(fv[numeric_columns])
    poly_feature_names = poly.get_feature_names_out(numeric_columns)
    poly_df = pd.DataFrame(poly_features, columns=poly_feature_names)
    fv_with_poly = pd.concat([fv.reset_index(drop=True), poly_df], axis=1)
    fv_with_poly = fv_with_poly.loc[:, ~fv_with_poly.columns.duplicated()]
    st.write(fv_with_poly.head())

    # SMOTE for Handling Imbalanced Dataset
    st.markdown("### SMOTE for Handling Imbalanced Dataset")
    smote = SMOTE(sampling_strategy=1)
    fv1, cv1 = smote.fit_resample(fv_with_poly, cv)
    st.write(pd.Series(cv1).value_counts())

    # Data Splitting
    st.markdown("### Data Splitting")
    x_train, x_test, y_train, y_test = train_test_split(fv1, cv1, test_size=0.2, random_state=42)

    # Scaling
    st.markdown("### Scaling")
    std = StandardScaler()
    x_train_std = std.fit_transform(x_train)
    x_test_std = std.transform(x_test)
    st.code("""
    std = StandardScaler()
    x_train_std = std.fit_transform(x_train)
    x_test_std = std.transform(x_test)
    """)

    st.markdown("## Hyperparameter Tuning using OPTUNA")
    
    # Define the objective function for Optuna
    st.code("""
    import numpy as np
    import optuna
    from sklearn.svm import SVC
    from sklearn.linear_model import LogisticRegression
    from sklearn.model_selection import cross_validate
    from sklearn.preprocessing import StandardScaler
    
    # Check for NaN or infinite values in the data
    assert not np.any(np.isnan(x_train_std)), "Input data contains NaN values"
    assert not np.any(np.isnan(y_train)), "Target data contains NaN values"
    assert not np.any(np.isinf(x_train_std)), "Input data contains infinite values"
    
    # Global lists to store training and validation scores for each trial
    training_scores = []
    validation_scores = []
    
    def objective(trial):
        # Log trial parameters for debugging
        print(f"Trial params: {trial.params}")
        
        algo = trial.suggest_categorical("algo", ["lor", "svc"])
    
        if algo == "svc":
            # Hyperparameters for SVC
            c = trial.suggest_float("C", 0.001, 1000, log=True)
            kernel = trial.suggest_categorical("kernel", ['linear', 'poly', 'rbf', 'sigmoid'])
    
            if kernel == 'poly':
                degree = trial.suggest_int("degree", 1, 3)
                model = SVC(C=c, kernel=kernel, degree=degree, random_state=42)
            elif kernel in ['rbf', 'sigmoid']:
                gamma = trial.suggest_categorical("gamma", ['scale', 'auto'])
                model = SVC(C=c, kernel=kernel, gamma=gamma, random_state=42)
            else:
                model = SVC(C=c, kernel=kernel, random_state=42)
        else:
            # Hyperparameters for Logistic Regression
            solver, penalty = trial.suggest_categorical(
                "choices", [
                    ("lbfgs", "l2"), ("newton-cg", "l2"),
                    ("sag", "l2"), ("saga", "l1"),
                    ("saga", "l2"), ("saga", "elasticnet")
                ]
            )
            reg_strength = trial.suggest_float("C", 0.001, 1000, log=True)
            l1_ratio = trial.suggest_float("l1_ratio", 0, 1) if penalty == "elasticnet" else None
    
            if penalty == "elasticnet":
                model = LogisticRegression(solver=solver, penalty=penalty, C=reg_strength, l1_ratio=l1_ratio, random_state=42)
            else:
                model = LogisticRegression(solver=solver, penalty=penalty, C=reg_strength, random_state=42)
    
        # Cross-validation scoring with training and validation
        try:
            scores = cross_validate(
                model, x_train_std, y_train, cv=5, 
                scoring="accuracy", return_train_score=True
            )
            train_score = scores["train_score"].mean()
            val_score = scores["test_score"].mean()
    
            # Append scores to global lists
            training_scores.append(train_score)
            validation_scores.append(val_score)
        except ValueError as e:
            print(f"Error during cross-validation: {e}")
            train_score, val_score = float("-inf"), float("-inf")
    
        return val_score
    
    # Running the optimization
    study = optuna.create_study(direction="maximize", sampler=optuna.samplers.TPESampler())
    study.optimize(objective, n_trials=100)
    
    # Plotting training vs. validation scores
    import matplotlib.pyplot as plt
    
    plt.figure(figsize=(10, 6))
    plt.plot(training_scores, label="Training Score", marker="o")
    plt.plot(validation_scores, label="Validation Score", marker="x")
    plt.xlabel("Trial")
    plt.ylabel("Accuracy")
    plt.title("Training vs. Validation Scores Across Trials")
    plt.legend()
    plt.grid()
    plt.show()
    
    # Display best trial
    print("Best Parameters:")
    print(study.best_params)
    
    """, language="python")

    st.markdown(
        """
        <div style="text-align: center;">
            <img src="https://cdn-uploads.huggingface.co/production/uploads/67441c51a784a9d15cb12871/FqUoV8hSyCWU3WocaqqGc.png" width="70%" />
        </div>
        """, 
        unsafe_allow_html=True
    )

    # Create the best model
    st.markdown("## Create the Model with the best algorithm and parameters you have received by perfroming Hyperparameter Tuning using Optuna")
    st.markdown("## SVC(kernel='poly', gamma = 'scale', C = 974.1963187644974, degree = 2)")
    model = SVC(kernel='poly', gamma = 'scale', C = 974.1963187644974, degree = 2)
    st.write(model)

    # Train the model
    st.markdown("### Train the Model")
    model.fit(x_train_std, y_train)

    # Model Evaluation
    st.markdown("# Model Evaluation")
    y_pred = model.predict(x_test_std)
    
    # Evaluation metrics
    st.write("Accuracy:", accuracy_score(y_test, y_pred))
    st.write("Classification Report:\n", classification_report(y_test, y_pred))
    st.write("Confusion Matrix:\n", confusion_matrix(y_test, y_pred))

    import streamlit as st
    import pandas as pd
    import seaborn as sns
    import matplotlib.pyplot as plt
    from sklearn.metrics import classification_report, confusion_matrix, accuracy_score
    
    # Example: Replace this with your actual test data and predictions
    y_pred = model.predict(x_test_std)
    
    # Calculate evaluation metrics
    conf_matrix = confusion_matrix(y_test, y_pred)
    class_report = classification_report(y_test, y_pred, output_dict=True)  # Output as a dictionary
    
    # Convert the classification report to a DataFrame
    class_report_df = pd.DataFrame(class_report).iloc[:-1, :-1]  # Exclude support and accuracy rows
    
    # Streamlit app
    st.title("Model Evaluation: Confusion Matrix and Classification Report")
    
    # Plotting with Matplotlib and Seaborn
    fig, axs = plt.subplots(1, 2, figsize=(16, 6))
    
    # Confusion Matrix Heatmap
    sns.heatmap(conf_matrix, annot=True, fmt="d", cmap="Blues", cbar=False, ax=axs[0], annot_kws={"size": 14})
    axs[0].set_title("Confusion Matrix", fontsize=16)
    axs[0].set_xlabel("Predicted Labels", fontsize=14)
    axs[0].set_ylabel("True Labels", fontsize=14)
    
    # Classification Report Heatmap
    sns.heatmap(class_report_df, annot=True, fmt=".2f", cmap="YlGnBu", cbar=False, ax=axs[1], annot_kws={"size": 12})
    axs[1].set_title("Classification Report", fontsize=16)
    axs[1].set_xlabel("Metrics", fontsize=14)
    axs[1].set_ylabel("Classes", fontsize=14)
    
    # Adjust layout
    plt.tight_layout()
    
    # Display the plots in Streamlit
    st.pyplot(fig)
    
    # Display additional metrics (optional)
    accuracy = accuracy_score(y_test, y_pred)
    st.success(f"**Accuracy:** {accuracy:.2f}")



else:
    st.warning("No Dataset Found")
background_image_url = "https://cdn-uploads.huggingface.co/production/uploads/67441c51a784a9d15cb12871/7ZCmkouk1pS37_kREZmYJ.jpeg"

# Apply custom CSS for the background image and overlay
st.markdown(
    f"""
    <style>
        .stApp {{
            background-image: url("{background_image_url}");
            background-size: auto;  /* Ensures the image retains its original size */
            background-repeat: repeat;  /* Makes the image repeat to cover the entire background */
            background-position: top left;  /* Starts repeating from the top-left corner */
            background-attachment: fixed;  /* Keeps the background fixed as you scroll */
        }}
        
        /* Semi-transparent overlay */
        .stApp::before {{
            content: "";
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.4);  /* Adjust transparency here (0.4 for 40% transparency) */
            z-index: -1;
        }}
        
        /* Container to center elements and limit width */
        .content-container {{
            max-width: 70%;  /* Limit content width to 70% */
            margin: 0 auto;  /* Center the container */
            padding: 50px;  /* Add some padding for spacing */
        }}

        /* Styling the markdown content */
        .stMarkdown {{
            color: white;  /* White text to ensure visibility */
            font-size: 100px;  /* Adjust font size for readability */
            # text-align: center;  /* Center align text */
        }}
    </style>
    """,
    unsafe_allow_html=True
)



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